private static final String MONGO_HOST = "xxx.xxx.xxx.xxx";

    private static final Integer MONGO_PORT = 27017;

    private static final String MONGO_DB = "testdb";

    public static void main(String args[]) {
        try {
            // 连接到 mongodb 服务
            MongoClient mongoClient = new MongoClient(MONGO_HOST, MONGO_PORT);

            // 连接到数据库
            MongoDatabase mongoDatabase = mongoClient.getDatabase(MONGO_DB);
            System.out.println("Connect to database successfully");

            // 创建Collection
            mongoDatabase.createCollection("test");
            System.out.println("create collection");

            // 获取collection
            MongoCollection<Document> collection = mongoDatabase.getCollection("test");

            // 插入document
            Document doc = new Document("name", "MongoDB")
                    .append("type", "database")
                    .append("count", 1)
                    .append("info", new Document("x", 203).append("y", 102));
            collection.insertOne(doc);

            // 统计count
            System.out.println(collection.countDocuments());

            // query - first
            Document myDoc = collection.find().first();
            System.out.println(myDoc.toJson());

            // query - loop all
            MongoCursor<Document> cursor = collection.find().iterator();
            try {
                while (cursor.hasNext()) {
                    System.out.println(cursor.next().toJson());
                }
            } finally {
                cursor.close();
            }

        } catch (Exception e) {
            System.err.println(e.getClass().getName() + ": " + e.getMessage());
        }
    }